TM 5-852-9/AFR 88-19, Vol. IX
CHAPTER 7
OPERATION AND MAINTENANCE
7-1. General. Good operation and maintenance manuals (O&M) are important because most arctic and
subarctic sites may be isolated by weather conditions for 2 to 3 weeks at a time. During these periods, the
survival of personnel at remote sites depends upon self-sufficient operation. Personnel rotation increases
training and maintenance problems; some incoming personnel may be inexperienced. Repair parts may be
scarce. Operation and maintenance manuals should cover the system components and should be explicit.
O&M manuals, such as the sample manual shown in appendix B, should be developed to supplement shop
drawings and equipment manuals prepared by the construction contractor. Additional manuals described
herein should be prepared by the designers to cover complete operation of the various systems. A manual
should describe how and why the system functions and what will happen if it is not operated as intended.
Operation and maintenance requirements vary among architectural, structural, mechanical, and electrical
systems. Specific aspects of each of these four systems are discussed in separate paragraphs below.
7-2. Architectural.
a. Exits. All exterior and exit doors should be kept in operable condition at all times. Snow and ice
should be cleared from stoops, steps, and walks leading to entrances. Door sills should be kept ice free, and
exterior doors, when not in use, should be completely closed to prevent drifting snow from entering
vestibules. Snow drifts covering first floor windows should be removed so potential exit routes are not
blocked in case of fire. High condensation on the surfaces and perimeters of exterior doors, especially
emergency exit doors that may not have frequent use, can freeze them shut. Therefore, infrequently opened
doors should be checked periodically for such icing.
b. Roof penetrations. Designers try to limit penetrations; therefore, no new roof penetrations should be
made for any reason until the proposed installation has been reviewed and approved by competent personnel.
Failure to conform to this direction can result in leakage within the building.
c. Roofs and roof drains. Roofs and roof drains should be kept clean and clear of debris at all times to
prevent water ponding of the roof. All debris (such as the cans, lumber, bottles, cardboard boxes, paper, rope,
broken glass, etc., which have been found on many roofs) should be removed and periodic examinations
should be performed. Nonessential foot traffic should be prohibited.
d. Removal of ice dams at eaves. Ice dams at the eaves should not be removed unless a problem exists
from ponded water or hazardous overhang. Hot water or steam may be used to melt channels to drain the
water behind the ice. Extreme care should be exercised when removing ice dams to avoid puncturing or
damaging the roof membrane or flashing.
e. Bird screens. Bird screens at intake and exhaust hood openings should be removed periodically for
cleaning and repair work. The screens should be kept free from frost buildup which reduces the hood capacity
and restricts system operation.
f. Ridge and eave vents. Normally, ridge and eave vents on buildings having cold attic spaces experience
little or no stoppage from snow or ice buildup; however, these vents should be regularly checked and physical
blockage should be eliminated. If these vents are closed or plugged up, personnel in charge of the facility
should be consulted to decide the method to be used to clear them, and maintenance should be performed
as soon as possible. A delay in clearing vents may result in water leakage from the attic or roof.
7-3. Structural.
a. Building design loadings. The design loadings for the building (wind, snow, seismic, floor loadings,
etc.) should be stated in the facility Operations and Maintenance Manual. If personnel from the using agency
do not know the design capacities, they sometimes become alarmed when the structure is subjected to a
heavier than normal loading. Heavy snow should not be removed unless it is clearly detrimental (overloading
the roof or endangering personnel or equipment). A roof designed for a load of 30 psf can safely support an
ice load approximately 8 inches thick over its entire surface. If it becomes necessary to remove snow from
the roof, leave the lower six inches of snow in place to avoid damaging the membrane. Also leave snow in
place around penetrations to protect the flashings. Personnel involved in snow removal shall not be placed
at risk. If loads in excess of design loadings are realized or contemplated, refer the problem to a structural
engineer for professional recommendations.
7-1
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